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51.
Coastline change detection using remote sensing 总被引:3,自引:3,他引:3
A. A. Alesheikh Assistant professor A. Ghorbanali N. Nouri 《International Journal of Environmental Science and Technology》2007,4(1):61-66
Coast is a unique environment in which atmosphere, hydrosphere and lithosphere contact each other. Coastline is one of the most important linear features on the earth’s surface, which display a dynamic nature. Coastal zone, and its environmental management requires the information about coastlines and their changes. This paper examines the current methods of coastline change detection using satellite images. Based on the advantages and drawbacks of the methods, a new procedure has been developed. The proposed procedure is based on a combination of histogram thresholding and band ratio techniques. The study area of the project is Urmia Lake; the 20th. largest, and the second hyper saline lake in the world. In order to assess the accuracy of the results, they have been compared with ground truth observations. The accuracy of the extracted coastline has been estimated as 1.3 pixels (pixel size=30 m). Based on this investigation, the area of the lake has been decreased approximately 1040 square kilometers from August 1998 to August 2001. This result has been verified through TOPEX/Posidon satellite information that indicates a height variation of three meters. 相似文献
52.
J. Nouri S. Toutounchian 《International Journal of Environmental Science and Technology》2004,1(2):109-117
Application of environmental management system (EMS) in urban environment provides a city with orderliness, regularity, quietness and freshness environment. Besides, it contributes sustainable development and optimization in life level index of the city. If the whole urban districts design and establish an environmental management system ISO 14001, the development will be faster and more sustainable. Municipality of Tehran, District 22 has been found and started an activity under the command of Sterling Council of Iran Urbanization and Architecture in order to regenerate the urbanization concealed concepts and also to control and organize the excessive constructions in west and northwest of Tehran since 2000. As a result of human undergoing development activities, the process of urbanization during many years has caused various environmental impacts. Thus, decision makers and managers considered urban sustainable development as a main strategy. District-22, has taken the required steps in providing sustainable development, safety and health of the organization and citizens in the related district. Environmental policy and commitment of top management (Mayor of the District-22) are to keep environmental conservation, in a well organized manner. In this study, dominant environmental aspects, impacts and legal requirements of the related activities and services are identified. Subsequently, environmental objectives and targets and also environmental management programs have been determined. Besides, training, internal and external communication, operational control, emergency preparedness and responsibility, obligations to follow environmental rules and achieving certification of ISO 14001; 1996 standard are the most important highlights at this study. The planning process, establishing and the method of operation has also been studied. 相似文献
53.
Flocculation of colloidal size fraction for Cu, Zn, Pb, Ni and Mn was investigated on a series of mixtures with water salinities
ranging from 1.5 to 9.5‰ during mixing of Haraz River with the Caspian Sea water. The flocculation trend of Zn (85.5%) > Mn
(55.2%) > Cu (39.6%) > Pb (33.7%) > Ni (11.3%) indicates that Cu, Zn, Pb and Mn have non-conservative behavior and Ni has
relatively conservative behavior during estuarine mixing. Highest flocculation of heavy metals occurs between salinities of
1.5 and 4.5‰. Statistical analysis indicates that the flocculation of Cu, Zn and Ni is governed by pH and total nitrogen. 相似文献
54.
Hamideh Rouhani Tazangi Ataallah Soltani Goharrizi Ebrahim Jahanshahi Javaran 《国际泥沙研究》2021,36(5):637-655
In the current study, the settling, interaction, drafting, kissing, and tumbling of two identical and non-identical circular particles were simulated in a two-dimensional box in shear-thinning, Newtonian, and shear-thickening fluids by using the combined lattice Boltzmann-smoothed profile methods. Furthermore, the drag coefficient of one particle settling for different power-law indexes and Archimedes numbers was calculated. Also, the effect of the diameter ratio of the two particle pairs was considered during settling. The developed method was validated by simulating the settling of one particle and two identical particles in a Newtonian fluid. To consider two non-identical particles, two cases were examined. In Case A, the larger particle was above the smaller one and in the Case B, the smaller particle was above the larger one. The results showed that the two non-identical particles were separated more easily than the identical ones. In the settling of two particles under the same Archimedes number, the drafting and kissing time considerably increased by changing the non-Newtonian fluid behavior from a shear-thinning one to a shear-thickening one. Also, when the larger particle was above the smaller one, the time duration of the kissing stage increased with the decrease in the diameter ratio. 相似文献